MOBILE INSTALLATION AND RESISTANCE BOARD WEIRS IN TOMMARPSÅN
On behalf of the County Administrative Board of Skåne, we installed our fish counter, TiVA FC, in Tommarpsån to monitor fish migration. At this location, there was no fixed structure available for mounting the fish counter, so we utilized mobile installation with our mobile fish counter tower along with a resistance board weirs solution to guide the fish through the fish counter.
FISH COUNTER TOWER
The fish counter tower we offer is made of stainless steel and has a wide base with four adjustable feet to be placed in a watercourse even if the bottom is not entirely level. The tower is 2 meters high and is suitable for watercourses with a depth of up to approximately 1.2 meters. The tower also features a winch for hoisting the counter out of the water for easy cleaning and maintenance. Additionally, the tower has multiple attachment points to secure devices like resistance board weirs.
RESISTANCE BOARD WEIRS
The design is a variation of a so-called “resistance board weirs”. They consist of a tube structure attached to the bottom of the watercourse. The grate itself comprises air-filled UV-resistant tubes, allowing it to float on its own. The key feature is the adjustable vane behind the tubes, which is lifted above the surface with the water’s pressure, preventing fish from swimming past the grate. When the grate get clogged, for example with leaves, it collects at the top of the grate and can be easily removed. If the vane is properly adjusted, the bars can even be self-cleaning. This functionality also allows canoes and kayaks to pass without issues, even if a large log were to come along.
Fish counter tower with floating bar racks in Tommarpsån 2021.
First few fishes to pass through the fish counter.